By Dr. Mercola|
First, it's important to understand that vitamin D3 is an oil soluble steroid hormone. It's formed when your skin is exposed to ultraviolet B (UVB) radiation from the sun (or a safe tanning bed). When UVB strikes the surface of your skin, your skin converts a cholesterol derivative in your skin into vitamin D3.
However, the vitamin D3 that is formed is on the surface of your skin does not immediately penetrate into your bloodstream. It actually needs to be absorbed from the surface of your skin into your bloodstream.
The critical question then is: how long does it take the vitamin D3 to penetrate your skin and reach your bloodstream?
If you're thinking about an hour or two, like I did until recently, you're wrong. Because new evidence shows it takes up to 48 hours before you absorb the majority of the vitamin D that was generated by exposing your skin to the sun!
Therefore, if you shower with soap, you will simply wash away much of the vitamin D3 your skin generated, and decrease the benefits of your sun exposure. So to optimize your vitamin D level, you need to delay washing your body with soap for about two full days after sun exposure.
Now not many people are not going to bathe for two full days.
However you really only need to use soap underneath your arms and your groin area. , so this is not a major hygiene issue. You'll just want to avoid soaping up the larger areas of your body that were exposed to the sun.
Other Reasons to Avoid the Shower
Avoiding the shower can also benefit your health in a number of other ways, because unless you have well water, you're showering in water from a municipal water supply that is loaded with chlorine,fluoride, disinfection by products, and pharmaceutical drugs that have made their way into the sewer system.
Chlorine, although it's best avoided as much as possible, is actually not the major issue. The biggest danger comes from the byproducts created when chlorine combines with organic material in the water.
These disinfection byproducts (DBPs), such as trihalomethanes (THMs) and haloacetic acids (HAAs) are EXTREMELY toxic. Some experts believe them to be over 10,000 times more toxic than chlorine. They're so dangerous, in fact, that the U.S. Environmental Protection Agency (EPA) sets the goal limit for some of them at zero. Unfortunately, it's impossible to enforce, which means you always have some in your municipal water supply.
DBPs have been linked to reproductive problems in both animals and humans, and human studies suggest that lifetime consumption of chlorine-treated water can more than double the risk of bladder and rectal cancers in certain individuals.
Unfortunately, studies have shown DBPs may wreak even more havoc when they're absorbed through your skin. For example, one study published in the Journal of Environmental Sciences last year found that swimming in a chlorinated pool presented an unacceptable cancer risk.
You can easily absorb as many DBP toxins in one shower as you would by drinking tap water all week long, so the less time you spend in the shower, the better.